Kimura Yuka, Tasaka Masao, Torii Keiko U, Uchida Naoyuki
Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8602, Japan.
Development. 2018 Jan 8;145(1):dev156380. doi: 10.1242/dev.156380.
The epidermal cell layer and the tissues that lie underneath have different intrinsic functions during plant development. The stem cells within the shoot apical meristem (SAM) that give rise to aerial structures are located in the epidermal and internal tissue layers. However, our understanding of how the functions of these stem cells are coordinated across tissue layers so stem cells can behave as a single population remains limited. WUSCHEL (WUS) functions as a master regulator of stem cell activity. Here, we show that loss of function in the ERECTA (ER)family receptor kinase genes can rescue the mutant phenotype of plants (loss of stem cells), as demonstrated by the reinstated expression of a stem cell marker gene in the SAM epidermis. Localized expression in the epidermis can suppress the SAM phenotype caused by loss of ER-family activity. Furthermore, the CLAVATA3- and cytokinin-induced outputs, which contribute to stem cell homeostasis, are dysfunctional in a tissue layer-specific manner in ER-family mutants. Collectively, our findings suggest that the ER family plays a role in the coordination of stem cell behavior between different SAM tissue layers.
在植物发育过程中，表皮细胞层及其下方的组织具有不同的内在功能。形成地上结构的茎尖分生组织（SAM）中的干细胞位于表皮和内部组织层中。然而，我们对于这些干细胞的功能如何在组织层之间协调，从而使干细胞能够作为一个单一群体发挥作用的理解仍然有限。WUSCHEL（WUS）作为干细胞活性的主要调节因子发挥作用。在此，我们表明，ERECTA（ER）家族受体激酶基因功能丧失可挽救植物的突变表型（干细胞丧失），这通过SAM表皮中干细胞标记基因的恢复表达得以证明。在表皮中的局部表达可抑制由ER家族活性丧失引起的SAM表型。此外，对干细胞稳态有贡献的CLAVATA3和细胞分裂素诱导的输出在ER家族突变体中以组织层特异性方式功能失调。我们的研究结果共同表明，ER家族在不同SAM组织层之间干细胞行为的协调中发挥作用。
